German is just fascinating!Look at what happens when we exchange the prefix in: Übersetzer (which means both translator and somebody who ferries you over, although literally it is "to sit above").
Über- means “over, above” and is sometimes even used in English to express a superlative. The opposite of “über” is "unter" - and indeed there is also one word where Unter is used with respect to language: subtitles are Untertitel.
But an Untersetzer is a coaster. Always.
An Übersetzer might use an Untersetzer – but the reverse is rarely the case. An Übersetzer must dransetzen (give it his all) everything to get the right message across (über) and if he does, he might end up as the total Überflieger! Flying above! But that requires stamina – Durchsetzungskraft or the power to “sit” (read “push”) through. Can I draufsetzen (add) one more? Or was the play with setzen and what the various prefixes do überzeugend (convincing)?